260 Higher Plants and Soil Microorganisms 



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8. Jensen, H. L., Bacterial treatment of non-leguminous seeds on agricultural 

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9. Katznelson, H., Lochhead, A. G., and Timonin, M. I., Soil microorganisms 

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10. Linford, M. B., Methods of obser\ing soil flora and fauna associated with 

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13. Neller, J. R., The influence of growing plants upon oxidation processes in 

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14. Nicol, H., Plant Growth Substances, Chemical Publishing Co., New York, 

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15. Parker-Rhodes, A. F., Preliminary experiments on the estimation of traces of 

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16. Schreiner, O., and Skinner, J. J., Nitrogenous soil constituents and their 

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17. Starkey, R. L., Some influences of the dexelopment of higher plants upon 

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